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Finding the Fourth Proportional to 68.78, 103.01 and 39.83

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Solution

The fourth proportional to 68.78, 103.01 and 39.83 is: 59.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    68.78 : 103.01 = 39.83 : x
  2. Step 2: Convert to fraction form
    68.78/103.01 = 39.83/x
  3. Step 3: Cross multiply
    68.78x = 103.01 × 39.83
  4. Step 4: Simplify right side
    68.78x = 4,102.17
  5. Step 5: Solve for x
    x = 4,102.17/68.78
  6. Step 6: Final answer
    x = 59.65

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.